CN2093382U - Linear displacement float-type flowmeter - Google Patents

Abstract

The utility model discloses a linear displacement float-type flowmeter belonging to a fluid flow measuring device. A float-type flowmeter is a common fluid flow measuring instrument. The outer shell of an existing float-type flowmeter forms a regular conical body, and thereby, the displacement of a float and flow form a non-linear relationship which is inconvenient for not only scale and observation, but also the requirement of linear long distance transmission. The inner side wall of the outer shell of the utility model forms a parabola rotation surface, and thereby, the displacement of the float and the flow changes form a linear relationship which is convenient for not only scale and observation, but also linear long distance transmission when necessary.

Description

Linear displacement float-type flowmeter

The utility model belongs to a kind of fluid flow rate measurement apparatus.

Suspended body flowmeter is a kind of of area flowmeter, because it is simple in structure, easy to use, therefore, is widely used in each engineering department.

Its principle of work is, in a vertically arranged Rotary-table pipe big little down, places the float with definite shape and weight.When fluid flowed from bottom to top, fluid held up float at the acting force of the upper and lower pressure reduction of float to float, flows through the annular gap of fluid between float and pipe.When fluid to the apparent weight of acting force (this power from bottom to top) Yu the float of float (float in a vacuum weight and fluid media (medium) to the difference of the buoyancy of float) during balance, float suspends in fluid.At this moment, the fluid flow from annular gap flows through can be calculated as follows:

$q=c(F-F_o)\sqrt{\frac{2\mathrm{vf}(\mathrm{\ρf}-{\mathrm{\ρ}}_o)g}{F_o\·{\mathrm{\ρ}}_o}}$

……（1）

In the formula: the q-fluid volume flow

The C-efflux coefficient

The F-float suspends and locates area of section in the pipe

F ₀The area of section of-float maximum

The Vf-float volume

P ₀-fluid density

p _f-float density

G-acceleration of gravity

Because of shell is a Rotary-table, so have

F=π r ²And F=KL ²(2)

In the formula: the r-float suspends and locates the radius of tube wall

L-float suspension height (apart from the vertex of a cone)

The K-constant

With formula (2) substitution (1), simplify:

q＝K ₀·L ²－K ₁……（3）

In the formula: K ₀.K ₁-be constant down for set pipe and float

Know that by (3) formula the float suspension height is decided with fluid flow.Therefore, the observation float height that suspends can be determined fluid flow.The principle of work and the characteristics of Here it is existing suspended body flowmeter.

The shortcoming of prior art just is that as previously mentioned, its shell pipe is inverted Rotary-table.Therefore, must occur suc as formula (3) such q and L, promptly the displacement of flow and float is non-linear.This had just both made inconvenience scale when making, and made observation inconvenience again, and it is then more inconvenient to do linear teletransmission as need.

The purpose of this utility model just is that it is the flow scale line that a kind of float suspension height L(is provided) and the linear suspended body flowmeter of fluid flow q.

The purpose of this utility model is achieved in that shell with suspended body flowmeter by positive Rotary-table, the para-curve stage body that to change its side into be the para-curve surfaces of revolution.This para-curve meets: $r=\sqrt{K_3.L}$ Or r ²=K ₃L ... (4)

In the formula: K ₃-constant

Get final product.

Be not difficult to find out that formula (4) substitution formula (1) will be had

q

L

The displacement that is float is directly proportional with flow, and the flow scale line is linear change.

Below in conjunction with accompanying drawing the utility model is further described.Fig. 1 is one of the utility model type.Among the figure: the 1-shell; The 2-float; The 3-cover plate; The 4-guide pipe; The 5-spacing ring; The transparent sighting tube of 6-; 7-flow scale scale; The 8-steady arm; The 9-bar; The 10-air relief cock.

The shell of suspended body flowmeter is a reducing, special-shaped triangle.Its three interfaces have flange to link to each other with the outside, and the bottom is fluid intake A, and sidepiece is fluid egress point B, and the top links to each other with the cover plate of flowmeter.Move corresponding position (in a, the b scope) suspending with float, the outside is a housing internal diameter and its place height tool $r=\sqrt{K_3.L}$ (r--housing internal diameter; L-place height; K ₃-constant) or r=K ₃The para-curve platform cone (para-curve rotary body) of the relation of L.Fixed guide pipe 4 and transparent sighting tube 6 are installed flow scale scale 7 on the cover plate 3 outside transparent sighting tube, at guide pipe bottom fixed locator 8.Float is that a dish dress thing 2 and a shaft 9 are formed, fixing spacing ring 5 on bar 9.

When fluid flows into from bottom A place and since fluid at pressure reduction the cause fluid of dish 2 about to coiling 2 acting force, it is suspended, fluid from housing and the gap between coiling flow through, flow out to the B place.Housing 1 progressively increases from bottom to top with the area of the annular gap of dish 2, because housing is γ ²=K ₃The para-curve rotary body of L, so its area of section is directly proportional with L.For set float, annular gap up and down pressure reduction is just set, and corresponding rate of flow of fluid is set, and therefore, float suspension height L will be directly proportional with the size of flow q value, observes the variation that just is directly proportional with fluid flow of the height of bar 9 at transparent sighting tube 5 places.

The advantage of the utility model protrusion just is that float suspension height and fluid flow size are linear change as mentioned above, the scale standard, and observation is accurately.As the need remote transfer signal, also be linear change, be convenient to be provided with secondary instrument.

Fig. 2 is another embodiment of the present utility model.Its structure is similar to conventional glass tube suspended body flowmeter, and difference is to change glass tube into the para-curve rotary body to get final product, and its principle and the foregoing description just repeat no more together.

Claims (3)

1, described linear displacement suspended body flowmeter, it has the shell (1) of a vertical likeness in form reduced flange threeway of installing, (A) flows into fluid from the bottom, (B) flows out from the side, cover plate (3) capping of its top, on the cover board along fixing transparent sighting tube (6) of cover plate center line and guide pipe (4), they are respectively outwards with to projecting inward, a discoid float of horizontal suspended (2) below the guide pipe in housing, fix a columniform bar (9) at float upper edge float center line, bar (9) is protruding upward from float (2), insert in guide pipe (4) and the transparent sighting tube (6), at bar (9) middle part fixedly spacing ring (5) to limit float displacement, and the suspended position of float is limited between the bottom tube wall of fluid intake (A) and fluid egress point (B), it is characterized in that fluid suspends from A float when B flows, and the displacement of float and fluid flow are linear.

2, linear displacement suspended body flowmeter according to claim 1 is characterized in that and the corresponding shell of float displacement scope that its inwall is the para-curve surfaces of revolution, is linear relationship to guarantee float displacement amount and fluid flow.

3, according to claim 1 and 2 described linear displacement suspended body flowmeters, it is characterized in that for measuring low discharge when shell is made of transparent materials such as glass, housing needn't be made threeway, only need make one vertically arranged, its inwall is the pipe of the para-curve surfaces of revolution, fluid flows through from bottom to top, directly gets final product at the housing high scale, and the cover plate (3) for guiding bar (9) of usefulness and top on the float, guide pipe (4), transparent sighting tube (6) etc. all can save.

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